Chapter 7
Behind the Net: The Untold History of the ARPANET and Computer Science
By Michael Hauben
hauben@columbia.edu
The global Internet's progenitor was the Advanced Research Projects
Agency Network (ARPANET) financed and encouraged by the U.S. Department
of Defense. This is important to remember, because the support and style
of management by ARPA of its contractors was crucial to the success of
the ARPANET. As the Internet develops and the struggle over the role it
plays unfolds, it will be important to remember how the network
developed and the culture with which it was connected. The culture of
the Net As a facilitator of communication, is important feature to
understand.
The ARPANET Completion Report, published jointly in 1978 by BBN of
Cambridge, Massachusetts, and ARPA, concludes by stating:
"...it is somewhat fitting to end on the note that the ARPANET
program has had a strong and direct feedback into the support and
strength of computer science, from which the network itself
sprung."(1)
In order to understand the wonder that the Internet and various other
components of the Net represent, we need to understand why the ARPANET
Completion Report ends with the suggestion that the ARPANET is
fundamentally connected to and born of computer science rather than of
the military.
PART I: The history of ARPA leading up to the ARPANET
A climate of scientific research surrounded the entire history of
the ARPANET. ARPA was formed to fund basic research, and thus was not
oriented toward military products. The formation of this agency was part
of the U.S. Government response to the then Soviet Union's launch of
Sputnik in 1957.(2). One area of ARPA supported research concerned the
question of how to utilize the military's investment in computers to do
Command and Control Research (CCR). Dr. J.C.R. Licklider was chosen to
head this effort. Licklider came to ARPA from BBN in October 1962.(3)
His educational background was a combination of engineering studies and
physiological psychology. His multidiscilinary experiences provided
Licklider with an unusual perspective uncommon among engineers.
As a result of Licklider's arrival, the Agency's contracts were
shifted from independent corporations towards "the best academic
computer centers."(4) The then current method of computing was via batch
processing. Licklider saw improvements could be made in CCR only from
work that would advance the current state of computing technology. He
particularly wanted to move forward into the age of interactive
computing, and the Defense Department contractors were not moving in
that direction. In an interview, Licklider described how at one of the
contractors, System Development Corporation (SDC) the computing research
being done "was based on batch processing, and while I was interested in
a new way of doing things, they [SDC] were studying how to make
improvements in the ways things were done already."(5) To reflect the
changed direction Licklider was bringing to ARPA supported research, his
division of ARPA was renamed Information Processing Techniques Office
(IPT or IPTO). The office "developed into a far-reaching basic research
program in advanced technology."(6)
The Completion Report states that "Prophetically, Licklider
nicknamed the group of computer specialists he gathered the
`Intergalactic Network'."(7) Before work on the ARPANET began, the
foundation had been established by the creation of the Information
Processing Techniques Office of ARPA. Robert Taylor, Licklider's
successor at the IPTO, reflects on how this foundation was based on
Licklider's interest in interconnecting communities. "Lick was among the
first to perceive the spirit of community created among the users of the
first time-sharing systems...." Taylor continues, "In pointing out the
community phenomena created, in part, by the sharing of resources in one
timesharing system, Lick made it easy to think about interconnecting the
communities, the interconnection of interactive, on-line communities of
people, ..."(8)
The "spirit of community" was related to Licklider's interest in
having computers help people communicate with other people.(9)
Licklider's vision of an "intergalactic network" connecting people
represented an important conceptual shift in computer science. This
vision guided the researchers who created the ARPANET. After the ARPANET
was functioning, the computer scientists using it realized that
assisting human communication was a major fundamental advance that the
ARPANET made possible.
As early as 1963, a commonly asked question of the IPTO
directors by the ARPA directors about IPTO projects was "Why
don't we rely on the computer industry to do that?", or occasionally
more strongly, "We should not support that effort because
ABC (read, "computer industry") will do it - if it's worth
doing!"(10) This question leads to an important distinction - this ARPA
research was different from what the computer industry had in mind to do,
or was likely to undertake. Since Licklider's creation of the IPTO, the
work supported by ARPA/IPTO continued his explicit emphasis on
communications. The Completion Report explains:
"The ARPA theme is that the promise offered by the computer
as a communication medium between people, dwarfs into relative
insignificance the historical beginnings of the computer
as an arithmetic engine."(11)
The Completion Report goes on to differentiate the research ARPA
supported from the research done by the computer industry:
"The computer industry, in the main, still thinks of the
computer as an arithmetic engine. Their heritage is reflected
even in current designs of their communication systems.
They have an economic and psychological commitment to the
arithmetic engine model, and it can die only slowly...."(12)
The Completion Report further analyzes this problem by tracing it
back to the nation's universities:
"...furthermore, it is a view that is still reinforced by
most of the nation's computer science programs. Even universities,
or at least parts of them, are held in the grasp of
the arithmetic engine concept...."(13)
ARPA's IPTO was responsible for the research and development
which led to the success of first the ARPANET, and later the
Internet. Without the commitment that existed via this support,
such a development might never have happened. One of ARPA's
criterion for supporting research was that the research had to be
of such a level as to offer an order of magnitude of advance over
the current state of development. Such research is never immediately
profitable. In society therefore there is the need for organizations
which do not pursue profit as their goal, but rather work on furthering
the state of the art. Computer networking was developed and spread widely
in an environment outside of commercial and profit considerations, an
environment that supported such research.
Others have understood the communications promise of computers. For
example, in RFC-1336, David Clark, senior research scientist at MIT's
Laboratory for Computer Science, is quoted,
"It is not proper to think of networks as connecting computers.
Rather, they connect people using computers to mediate.
The great success of the internet is not technical, but in
human impact. Electronic mail may not be a wonderful advance
in Computer Science, but it is a whole new way for people to
communicate. The continued growth of the Internet is a
technical challenge to all of us, but we must never loose
sight of where we came from, the great change we have worked
on the larger computer community, and the great potential we
have for future change."(14)
Research predating the ARPANET had been done by Paul Baran, Thomas
Marill and others.(15) This led Lawrence Roberts and other IPTO staff to
formally introduce the topic of networking computers of differing types
(i.e., incompatible hardware and software) together in order to make it
possible for ARPA's Principal Investigators (PI) to share resources.
The ARPA Principal Investigators meeting was held annually for university
and other contractors to summarize results of the previous year and
discuss future research. In the Spring of 1967, it was held at the
University of Michigan, in Ann Arbor. Networking was one of the topics
brought up at this meeting. As a result of discussion at this meeting, it
was decided that there had to be agreement on conventions for character
and block transmission, error checking and retransmission, and computer
and user identification. These specifications became the contents of the
inter-host communication's "protocol." Frank Westervelt was chosen to
write about this protocol and a communication group was formed to study
the questions.(16)
In order to develop a network of varied computers, two main problems
had to be solved:
1. To construct a 'subnetwork' consisting of telephone circuits and
switching nodes whose reliability, delay characteristics, capacity,
and cost would facilitate resource sharing among computers on the
network.
2. To understand, design, and implement the protocols and
procedures within the operating systems of each connected
computer, in order to allow the use of the new subnetwork by
the computers in sharing resources.(17)
After one draft and additional work on this communications
position paper were completed, a meeting was scheduled in early
October 1967 by ARPA at which the protocol paper and specifications
for the Interface Message Processor (IMP) were discussed. A
subnetwork of IMPs, dedicated mini-computers connected to each of
the participant computers, was the method chosen to connect the
participants's computers (hosts) to each other via phone lines.
This standardized the subnet to which the hosts connected. Now,
only the connection of the hosts to the network would depend on
vendor type, etc. ARPA had picked 19 possible participants in
what was now known as the "ARPA Network."
From the time of the 1967 PI Meeting, various computer
scientists who were ARPA contractors were busy thinking about
various aspects which would be relevant to the planning and
development of the ARPANET. Part of that work was a document
outlining a beginning design for the IMP subnetwork. This specification
led to a competitive procurement for the design of the
IMP subnetwork.
By late 1967 ARPA had given a contract to the Stanford
Research Institute (SRI) to write the specifications for the
communications network they were developing. In December of 1968,
SRI issued a report "A Study of Computer Network Design Parameters."
Elmer Shapiro played an important role in the research for
this report. Based on this work, Roberts and Barry Wessler of
ARPA wrote the final ARPA version of the IMP specification.(18) This
specification was ready to be discussed at the June, 1968 PI meeting.
The Program Plan, "Resource Sharing Computer Networks," was
submitted June 3, 1968 by the IPTO to the ARPA Director, who with
unusual speed, approved it on June 21, 1968. It outlined the objectives
of the research, and the plan of how the objectives would be fulfilled.
The purposed network was impressive as it would prove useful to both the
computing research centers which connected to the network and the
military. The proposed requirements for the research would provide
immediate benefits to the computer centers the network would connect.
ARPA's stated objectives were to experiment with varied interconnections
of computers and the sharing of resources in an attempt to improve
productivity of computer research. Justification was drawn from
technical needs in both the scientific and military environments. The
Program Plan developed into a set of specifications. These
specifications were connected to a competitive Request for Quotation
(RFQ) to find an organization which would design and build the IMP
subnetwork.(19)
Following the approval of the Program Plan, 140 potential bidders
were mailed the Request for Quotation. After a bidders conference, twelve
proposals were received and from them ARPA narrowed the bidders down to
four. BBN was the eventual recipient of the contract.(20)
The second technical problem, as defined by the ad hoc
Communications Group, still remained to be solved. The set of
agreed upon communications settings (known as a protocol), which
would allow the hosts to communicate with each other over the
subnetwork, had to be developed. This work was left "for host
sites to work out among themselves."(21) This meant that the software
necessary to connect the hosts to the IMP subnetwork had to be developed.
ARPA assigned this duty to the initially designated ARPANET sites. Each
of the first sites had a different type of computer to connect. ARPA
trusted that the programmers at each site would be capable of modifying
their operating systems in order to connect their systems to the
subnetwork. In addition the sites needed to develop the software
necessary to utilize the other hosts on the network. By assigning them
responsibilities, ARPA made the academic computer science community an
active part of the ARPANET development team.(22)
Steve Crocker, one of graduate students involved with the
development of the earliest ARPANET protocols, associates the
placement of the initial ARPANET sites at research institutions
with the fact that the ARPANET was ground-breaking research. He
wrote in a message responding to questions on the COM-PRIV mailing list:
"During the initial development of the Arpanet, there was
simply a limit as to how far ahead anyone could see and
manage. The IMPs were placed in cooperative ARPA R&D sites
with the hope that these research sites would figure out how
to exploit this new communication medium."(23)
The first sites of the ARPANET were picked to provide either
network support services or unique resources. The key services
the first four sites provided were(24):
UCLA - Network Measurement Center
SRI - Network Information Center
UCSB - Culler-Fried interactive mathematics
UTAH - graphics (hidden line removal)
Crocker recounts that the reason for selecting these particular four
sites was because they were "existing ARPA computer science research
contractors." This was important because "the research community could
be counted on to take some initiative."(25)
The very first site to receive an IMP was UCLA. Professor
Leonard Kleinrock of UCLA was involved with much of the early
development of the ARPANET. His work in queuing theory gave him a
basis to develop measurement techniques used to monitor the
ARPANET's performance. This made it natural to make sure that
UCLA received one of the first nodes as it would be important to
measure the network's activity from early on. In order for the
statistics to have correct data and for analysis purposes - one of
the first two or three sites had to be the measurement site. Sure
enough, UCLA was assigned to be the Network Measurement Center
(NMC).(26)
Part II. The Network Working Group
Once the initial sites were picked, representatives from
each site gathered together to start talking about solving the
technical problem of getting the hosts to communicate with each
other. The ARPANET Completion Report tells us about this beginning:
"To provide the hosts with a little impetus to work on the
host-to-host problems. ARPA assigned Elmer Shapiro of SRI
'to make something happen', a typically vague ARPA assignment.
Shapiro called a meeting in the summer of 1968 which
was attended by programmers from several of the first hosts
to be connected to the network. Individuals who were present
have said that it was clear from the meeting at that time,
no one had even any clear notions of what the fundamental
host-to-host issues might be."(27)
This group, which came to be known as the Network Working Group
(NWG), was exploring new territory. The first meeting took place several
months before the first IMP was configured. The group had to think from a
blank slate. In Crocker's recollections of the important developments
produced by the NWG provided as the introduction to RFC-1000, the reader
is reminded that the thinking involved was groundbreaking and thus
exciting. Crocker remembers that the first meeting was chaired by Elmer
Shapiro of SRI, who initiated the conversation with a list of
questions.(28) Also present at this first meeting were Steve Carr from
the University of Utah, Stephen Crocker from UCLA, Jeff Rulifson from
SRI, and Ron Stoughton from UCSB. These attendees, most of them graduate
students, were the programmers described in the ARPANET Completion
Report.
According to Crocker, this was a seminal meeting. The attendees
could only be theoretical, as none of the lowest levels of communication
had been developed yet. They needed a transport layer or low-level
communications platform to build upon. BBN would not deliver the first
IMP until August 30, 1969. It was important to meet before this date, as
the NWG "imagined all sorts of possibilities."(29) Only once their
thought processes started could this working group actually develop
anything. These fresh thoughts from fresh minds helped to incubate new
ideas. The ARPANET Completion Report properly acknowledges what this
early group helped accomplish. "Their early thinking was at a very high
level."(30) A concrete decision of the first meeting was to continue
holding meetings similar to the first one. This wound up setting the
precedent of holding exchange meetings at each of their sites.
Crocker, describing the problems facing these networking pioneers,
writes:
"With no specific service definition in place for what the
IMPs were providing to the hosts, there wasn't any clear
idea of what work the hosts had to do. Only later did we
articulate the notion of building a layered set of protocols
with general transport services on the bottom and multiple
application-specific protocols on the top. More precisely,
we understood quite early that we wanted quite a bit of
generality, but we didn't have a clear idea how to achieve
it. We struggled between a grand design and getting something
working quickly."(31)
The initial protocol development led to DEL (Decode-Encode-Language)
and NIL (Network Interchange Language). These languages were more
advanced than what was needed or possible at the time. The basic purpose
was to form an on-the-fly description that would tell the receiving end
how to understand the information that would be sent. This first set of
meetings were extremely abstract as neither ARPA nor the universities had
conceived of any official charter. However, the lack of a specific charter
allowed the group to think broadly and openly.
BBN did provide details about the host-IMP interface specifications
from the IMP side. This information gave the group some definite starting
points to build from. Soon after BBN provided more information, on
Valentine's Day, 1969, members of the NWG, members of BBN and members of
the Network Analysis Corporation (NAC) met for the first time. The NAC
had been invited because it had been contracted by ARPA to specify the
topological design of the ARPANET and to analyze its cost, performance,
and reliability characteristics.(32) As all the parties had different
priorities in mind, the meeting was a difficult one. BBN was interested
in the lowest level of making a reliable connection. The programmers from
the host sites were interested in getting the hosts to communicate with
each either via various higher level programs. Even when the crew from
BBN did not turn out to be the "experts from the East," members of the
NWG still expected that "a professional crew would show up eventually to
take over the problems we were dealing with."
A step of great importance which began the open documentation
process occurred as a result of a "particularly delightful" meeting
that took place a month later in Utah. The participants decided
it was time to start recording their meetings in a consistent fashion.
What resulted was a set of informal notes titled "Request for Comments,"
(RFC). Stephen Crocker writes about their formation:
"I remember having great fear that we would offend whomever
the official protocol designers were, and I spent a sleepless
night composing humble words for our notes. The basic
ground rules were that anyone could say anything and that
nothing was official. And to emphasize the point, I labeled
the notes 'Request for Comments.' I never dreamed these
notes would be distributed through the very medium we were
discussing in these notes. Talk about Sorcerer's Apprentice!"(33)
Crocker replaced Shapiro as the Chairman of the NWG soon
after the initial meeting. He describes how they wrestled with
the creation of the host-host protocols:
"Over the spring and summer of 1969 we grappled with the
detailed problems of protocol design. Although we had a
vision of the vast potential for intercomputer communication,
designing usable protocols was another matter. A
custom hardware interface and custom intrusion into the
operating system was going to be required for anything we
designed, and we anticipated serious difficulty at each of
the sites. We looked for existing abstractions to use. It
would have been convenient if we could have made the network
simply look like a tape drive to each host, but we knew that
wouldn't do."(34)
The first IMP was delivered to UCLA in late August, 1969.
The next was delivered to SRI a month later in October.(35) Once more
than one IMP existed, the NWG had to implement a working communications
protocol. This first set of pairwise host protocols included remote login
for interactive use (telnet), and a way to copy files between remote
hosts (FTP). Crocker writes:
In particular, only asymmetric, user-server relationships
were supported. In December 1969, we met with Larry Roberts
in Utah, [and he] made it abundantly clear that our first
step was not big enough, and we went back to the drawing
board. Over the next few months we designed a symmetric
host-host protocol, and we defined an abstract implementation
of the protocol known as the Network Control Program.
("NCP" later came to be used as the name for the protocol,
but it originally meant the program within the operating
system that managed connections. The protocol itself was
known blandly only as the host-host protocol.) Along with
the basic host-host protocol, we also envisioned a hierarchy
of protocols, with Telnet, FTP and some splinter protocols
as the first examples. If we had only consulted the ancient
mystics, we would have seen immediately that seven layers
were required.(36)
The Network Working Group went on to develop the protocols
necessary to make the network viable. The group swelled in attendance as
more and more sites connected to the ARPANET. The group became large
enough (around 100 people) that one meeting was held in conjunction with
the 1971 Spring Joint Computer Conference in Atlantic City. A major
test of the NWG's work came in October 1971, when a meeting was
held at MIT. Crocker continues the story:
"[A] major protocol "fly-off" - Representatives from each
site were on hand, and everyone tried to log in to everyone
else's site. With the exception of one site that was completely
down, the matrix was almost completely filled in,
and we had reached a major milestone in connectivity."(37)
The NCP was creating what was called the "host to host protocol."
Explaining why this was important, the authors of the ARPA draft write:
"The problem is to design a host protocol which is sufficiently
powerful for the kinds of communication that will
occur and yet can be implemented in all of the various
different host computer systems. The initial approach taken
involved an entity called a "Network Control Program" which
would typically reside in the executive of a host, such that
processes within a host would communicate with the network
through this Network Control Program. The primary function
of the NCP is to establish connections, break connections,
switch connections, and control flow. A layered approach was
taken such that more complex procedures (such as File Transfer
Procedures) were built on top of similar procedures in
the host Network Control Program."(38)
As the ARPANET grew, the number of users bypassed the number
of developers. This signaled the success of these networking
pioneers. Steve Crocker appointed Alex McKenzie and Jon Postel to
replace him as Chairmen of the Network Working Group. The Completion
Report details how this role changed:
"McKenzie and Postel interpreted their task to be one of
codification and coordination primarily, and after a few
more spurts of activity the protocol definition process
settled for the most part into a status of a maintenance
effort."(39)
ARPA was a management body which funded academic computer
scientists. ARPA's funding paved the way for these scientists to
create the ARPANET. BBN helped by developing the packet switching
techniques which served as the bottom level of transmitting
information between sites. The NWG provided an important development
in its "Request for Comments" documentation which made possible the
developing new protocols.
PART III. About RFC's as "Open" Documentation
The open exchange of ideas initiated from the very first meeting of
the Network Working Group was continued in the Request For Comments. As
meeting notes, the RFC's were meant to keep members updated on the status
of various developments and ideas. They were also meant to gather
responses from people. RFC-3, "Documentation Conventions," documents the
"rules" governing the production of these notes. Heading RFC-3 are the
open distribution rules:
"Documentation of the NWG's effort is through notes such as
this. Notes may be produced at any site by anybody and
included in this series."(40)
These opening sentences invite anyone willing to be helpful into
the protocol definition process. This is important because all
restrictions are lifted by these words, allowing for the open
process aimed for. The guide goes on to describe the rules
concerning the contents of the RFC's:
"The content of a NWG note may be any thought, suggestion,
etc. related to the HOST software or other aspect of the
network. Notes are encouraged to be timely rather than
polished. Philosophical positions without examples or other
specifics, specific suggestions or implementation techniques
without introductory or background explication, and explicit
questions without any attempted answers are all acceptable.
The minimum length for a NWG note is one sentence."(41)
In RFC-3, Crocker continues to explain the philosophy behind the
perhaps unprecedented openness represented:
"These standards (or lack of them) are stated explicitly for
two reasons. First, there is a tendency to view a written
statement as ipso facto authoritative, and we hope to promote
the exchange and discussion of considerably less than
authoritative ideas. Second, there is a natural hesitancy to
publish something unpolished, and we hope to ease this
inhibition."(42)
[The entire RFC-3 is reproduced in the Appendix.]
This open process encouraged and led to the exchange of information.
Technical development is only successful when information is allowed to
flow freely and easily between the parties involved. Encouraging
participation is the main principle that made the development of the Net
possible.
Statements like the ones contained in RFC-3 are democratic in their
support of a process of openness. They were written during the late
1960s, a time of popular protest for freedom of speech. People were
demanding more of a say in how their countries were run. The open
environment needed to develop new technologies is consistent with the
cry for more democracy which students and others were raising during the
1960s throughout the world. What is amazing is the collaboration of the
NWG (mostly graduate students) and ARPA (a component of the military)
during the 1960s and 1970s. This seems unusual given the context of the
times, e.g., the student anti-war movement. Robert Braden of the
Internet Activities Board reflects on this collaboration:
"For me, participation in the development of the ARPAnet and
the Internet protocols has been very exciting. One important
reason it worked, I believe, is that there were a lot of
very bright people all working more or less in the same
direction, led by some very wise people in the funding
agency. The result was to create a community of network
researchers who believed strongly that collaboration is more
powerful than competition among researchers. I don't think
any other model would have gotten us where we are today."(43)
Such collaboration is why the work of these computer scientists led to
such an amazing and democratic achievements, the Net and the cooperative
culture of the Net.(44)
Calling these notes a "Request for Comment" established a
fascinating tradition. It predates the Usenet post, which in a fashion
could also be called a "request for comment." Both are the presentation
of a particular person's ideas, questions or comments to the general
public for comments, criticism or suggestions. Early RFC's established
this tradition. Many RFC's are in fact comments on previous RFC's.(45)
Part IV: Conclusion
How were the developments of the ARPANET made possible? None of the
participants had previous solutions to any of the problems and tasks
that they faced to establish a working packet switched test bed with
host to host connectivity. They had to put much thought and work into
their research. As the resulting ARPANET was tremendously successful and
fulfilled the objectives of the project ARPA presented, it is important
to see what can be learned from the research and research methods from
which it emerged. Bernie Cosell, who worked at BBN during this early
period, describes the importance of an open process in a developmental
situation:
"*no*one* had the necessary expertise [and vision] to figure
any of this out on their own. The cultures among the early
groups were VERY different [--] multics, sigma-7, IBM ... at
Rand, ... PDP-10s at BBN and SRI... [and possibly] UCSB and
Utah had pdp-10's, too. The pie-in-the-sky applications
ranged over a WIDE landscape, with no one knowing quite
where it would lead. Some kind of free, cross-cultural
info/idea exchange *had* to happen."(46)
The computer scientists and others involved were encouraged
in their work by ARPA's philosophy of gathering the best computer
scientists working in the field and supporting them:
"IPT usually does little day-to-day management of its contractors.
Especially with its research contracts, IPT would not be producing
faster results with such management as research must progress at its
own pace. IPT has generally adopted a mode of management which
entails finding highly motivated, highly skilled contractors, giving
them a task, and allowing them to proceed by themselves."(47)
The work of the Network Working Group was vital to the
development of the ARPANET. Vint Cerf, another of the graduate
students involved with the early protocol development and still
closely connected to the Internet, echoed this sentiment when he
opened his paper "An Assessment of ARPANET Protocols," by writing:
"The history of the Advanced Research Project Agency resource
sharing computer network (ARPANET) is in many ways a history
of the study, development, and implementation of protocols."(48)
Cerf supports Cosell's opinion about the uncertainty and newness of the
entire project:
"The tasks facing the ARPANET design teams were often unclear,
and frequently required agreements which had never
been contemplated before (e.g., common protocols to permit
different operating systems and hardware to communicate).
The success of the effort, seen in retrospect, is astonishing,
and much credit is due to those who were willing to commit
themselves to the job of putting the ARPANET together."(49)
The NWG's work blazed the trail which the developers of the TCP/IP
suite of protocols (Transport Control Protocol/ Internet Protocol)
successfully followed when the need to expand and include other networks
based on other technologies than NCP arose. The principles embodied by
RFC-3 and the open RFC documentation process provided a strong foundation
which began with NCP and was continued by the work on TCP/IP. NCP was
developed in the field and versions of it were released early in its
development so various programmers could work on implementing and
improving the protocol. In addition all specifications were free and
easily available for people to examine and comment on. Through this
principle of early release, the problems and kinks were found and worked
out in a timely manner. The future developers of TCP/IP learned from the
developers of NCP a practice of developing from the bottom up. The
bottom-up model allows for a wide-range of people and experiences to join
in and perfect the protocol and make it the best possible.
The public funding of the ARPANET project meant that the
documentation could be made public and freely available. The
documentation was neither restricted nor classified. This open process
encouraging communication was necessary for these pioneers to succeed.
Research in new fields of study requires that researchers cooperate and
communicate in order to share their expertise. Such openness is
especially critical when no one person has the answers in advance. In
his article, "The Evolution of Packet Switching," Larry Roberts
described the public nature of the process.
"Since the ARPANET was a public project connecting many major
universities and research institutions, the implementation and
performance details were widely published."(50)
The people at the forefront of development of these protocols
were the members of the Network Working Group, many of whom
came from academic institutions, and who therefore had the
support and time needed for the research. In summing up the
achievements of the process that developed the ARPANET, the
ARPANET Completion Report Draft explains:
"The ARPANET development was an extremely intense activity in
which contributions were made by many of the best computer
scientists in the United States. Thus, almost all of the
"major technical problems" already mentioned received continuing
attention and the detailed approach to those problems changed
several times during the early years of the ARPANET effort."(51)
Fundamental to the ARPANET, as explained by the Completion Report,
was the discovery of a new way of looking at computers. The developers
of the ARPANET viewed the computer as a communications device rather
than only as an arithmetic device.(52) This new view made the building
of the ARPANET possible. This view came from the research conducted by
those in academic computer science. Such a shift in understanding the
role of the computer is fundamental to advancing computer science. The
ARPANET research has provided a rich legacy for the further advancement
of computer science and it is important that the significant lessons
learned be studied and used to further advance the study of computer science.
---------------------
Notes for CHAPTER 7
(1) Chapter III, p. 132, Section 2.3.4, ARPANET Completion Report,
F. Heart, A. McKenzie, J. McQuillan, D. Walden, Washington, D.C.,
1978. (Hereafter, ARPANET Completion Report)
(2) ARPANET Completion Report Draft, September 9, 1977, unpublished,
p. III-6. (Hereafter, Completion Report Draft)
(3) Ibid.
(4) Ibid., p. III-7.
(5) Interview by William Aspray and Arthur L. Norberg, Tape recording,
Cambridge, Massachusetts, 28 October 1988, OH 150, Charles Babbage
Institute, University of Minnesota, Minneapolis, Minnesota.
(6) Completion Report Draft, p. III-7.
(7) Ibid.
(8) Ibid., p. IlII-21.
(9) See for example J.C.R Licklider and Robert Taylor, "The Computer as
a Communication Device," In Memoriam: J.C.R. Licklider 1915-1990,
Digital Research Center, Palo Alto, Califirnia, August 7, 1990;
originally published in Science and Technology, April, 1968.
(10) Completion Report Draft, p. III-23
(11) Ibid., p. III-24.
(12) Ibid.
(13) Ibid.
(14) David Clark, RFC-1336.
(15) See Chapter 8 "The Birth and Development of the ARPANET." Also, see
F. Heart, A. McKenzie, J. McQuillan, D. Walden, ARPANET Completion
Report, Washington, D.C., 1978, Chapter III, section 1.1.2,
starting on page III-9.
(16) Completion Report Draft, pp. III-25 and III-26.
(17) ARPANET Completion Report, p. II-8.
(18) Completion Report Draft, p. III-32.
(19) Ibid., p. III-35 and ARPANET Completion Report, p. II-2.
(20) Completion Report Draft, p. III-35.
(21) Ibid., p. III-67.
(22) Ibid., p. III-39 and personal discussion with Alex McKenzie,
November 1, 1993.
(23) Email message to Com-Priv mailing list (com-priv@psi.com)
Subject "Re: RFC1000 (Partial response to part 1)"
Date: Nov 27, 1993.
(24) Vinto G.Cerf, private email corespondence, dated Nov 27, 1993.
Subject: "Re: Early Days of the ARPANET and the NWG".
(25) "The Origins of RFC's" by Stephen D. Crocker, is contained in RFC-
1000 by J. Reynolds and J. Postel, p. 1.
(26) The following quotes show some of the reasoning that went into the
choice of the initial ARPANET sites.
"CCN's [The Campus Computing Network of UCLA's] chance to
obtain a connection to the ARPANET was a result of the presence
at UCLA of Professor L. Kleinrock and his students, including S.
Crocker, J. Postel, and V. Cerf. This group was not only involved
in the original design of the network and the Host protocols, but
also was to operate the Network Measurement Center (NMC). For
these reasons the first delivered IMP was installed at UCLA, and
ARPA was thus able to easily offer CCN the opportunity for
connection." (Completion Report Draft, p. III - 689)
"UCLA was specifically asked to take on the task of a "Network
Measurement Center" with the objective of studying the performance
of the network as it was built, grown, and modified; SRI was
specifically asked to take on the task of a "Network Information
Center" with the objective of collecting information about the
network, about host resources, and at the same time generating
computer based tools for storing and accessing that collected
information. (Completion Report Draft, p. II-16)
"The accessibility of distributed resources carries with it the
need for an information service (either centralized or distributed)
that enables users to learn about those resources. This was
recognized at the PI [ed. Primary Instigators] meeting in Michigan
in the spring of 1967. At the time, Doug Engelbart and his
group at the Stanford Research Institute were already involved in
research and development to provide a computer-based facility to
augment human interaction. Thus, it was decided that Stanford
Research Institute would be a suitable place for a 'Network
Information Center' (NIC) to be established for the ARPANET. With
the beginning of implementation of the network in 1969, construction
also began on the NIC at SRI." (Completion Report Draft, p. III-60)
(27) Completion Report Draft, p. III-67.
(28) Email message to Com-Priv mailing list
Subject: "Re: RFC1000 (End of response to part 1)"
Date: Nov 27, 1993.
(29) RFC-1000.
(30) Completion Report Draft, p. III-67.
(31) Email message to Com-Priv mailing list
Subject "Subject: Re: RFC1000 (Response to part 2)"
Date: Nov 27, 1993.
(32) Completion Report Draft, p. III-30.
(33) RFC-1000, p. 3.
(34) Ibid.
(35) In RFC-1000, Stephen Crocker reports on the process of the
installation of the first IMP.
"[T]ime was pressing: The first IMP was due to be delivered to
UCLA September 1, 1969, and the rest were scheduled at monthly
intervals.
At UCLA we scrambled to build a host-IMP interface. SDS,
the builder of the Sigma 7, wanted many months and many dollars
to do the job.
Mike Wingfield, another grad student at UCLA, stepped in and
offered to get the interface built in six weeks for a few thousand
dollars. He had a gorgeous, fully instrumented interface working
in five and one half weeks. I was in charge of the software, and
we were naturally running a bit late. September 1 was Labor Day,
so I knew I had a couple of extra days to debug the software.
Moreover, I had heard BBN was having some timing troubles with
the software, so I had some hope they'd miss the ship date. And
I figured that first some Honeywell people would install the
hardware -- IMPs were built out of Honeywell 516s in those days
-- and then BBN people would come in a few days later to shake
down the software. An easy couple of weeks of grace.
BBN fixed their timing trouble, air shipped the IMP, and it
arrived on our loading dock on Saturday, August 30. They arrived
with the IMP, wheeled it into our computer room, plugged it in
and the software restarted from where it had been when the plug
was pulled in Cambridge. Still Saturday, August 30. Panic time
at UCLA.
The second IMP was delivered to SRI at the beginning of
October, and ARPA's interest was intense. Larry Roberts and
Barry Wessler came by for a visit on November 21, and we actually
managed to demonstrate a Telnet-like connection to SRI."
(36) RFC-1000, p. 4.
(37) Ibid.
(38) Completion Report Draft, p. II-24.
(39) Completion Report Draft, p. III-69.
(40) RFC-3, p.1.
(41) Ibid.
(42) Ibid.
(43) RFC-1336
(44) This democratic community is in danger of being fundamentally
altered. This study of the history of the development of the
ARPANET in conjunction with Chapter 2, "The Social Forces Behind
the Development of Usenet News" are meant to help people understand
where the Net has come from, in order to defend it, and try
to fight to keep it open and democratic - "the seventh wonder of
the world" as a recent ad called the Internet.
(45) Some examples of comments upon comments include:
RFC-1 Crocker, S. Host software 1969 April 7
RFC-65 Walden, D. Comments on Host/Host Protocol document #1
RFC-36 Crocker, S. Protocol notes 1970 March 16
RFC-38 Wolfe, S. Comments on network protocol from NWG/RFC #36
RFC-39 Harslem, E.; Heafner, J. Comments on protocol re: NWG/RFC#36
RFC-33 Crocker, S. New Host-Host Protocol 1970 February 12
RFC-47 Crowther, W. BBN's comments on NWG/RFC #33 1970 April 20
(46) Bernie Cosell, "Re: RFC1000 - Questions about the origins of ARPANET
Protocols 2/2," alt.folklore.computers, Nov. 23, 1993.
(47) Completion Report Draft, p. III-47.
(48) Vinton Cerf, "An Assessment of ARPANET Protocols," Infotech
Education Ltd., Stanford University, California
(49) Ibid.
(50) Lawrence Roberts, "The Evolution of Packet Switching," Proceedings
of the IEEE, Vol 66, no 11, November 1978, p. 267.
(51) ARPANET Completion Report, p. II-24.
(52) Completion Report Draft, p. III-24.
------------------------
Special thanks to Alexander McKenzie of BBN, Stephen Crocker of
TIS, and Vinton Cerf of CNRI for making research materials available.
---------------------------------------------------------------------
Last Updated: October 15, 1995
===============================================================
This article is a draft chapter from Michael Hauben's
and Ronda Hauben's netbook
titled "Netizens: On the History and Impact of Usenet and the Internet."
*Commercial use is prohibited*
Please send us any comments about this draft. Send comments to
both hauben@columbia.edu and rh120@columbia.edu.